* {
  box-sizing: border-box;
}

body {
  font-family: "Microsoft YaHei","宋体","Segoe UI", "Lucida Grande", Helvetica, Arial,sans-serif;
  background: #374954;
  color: white;
  text-align: center;
}

#main {
  position: relative;
  list-style: none;
  background: rgba(0, 0, 0, 0.3);
  font-weight: 400;
  font-size: 0;
  text-transform: uppercase;
  display: inline-block;
  padding: 0;
  margin: 50px auto;
}
#main li {
  font-size: 0.8rem;
  display: inline-block;
  position: relative;
  padding: 15px 20px;
  cursor: pointer;
  z-index: 5;
  min-width: 120px;
}

li {
  margin: 0;
}

.drop {
  overflow: hidden;
  list-style: none;
  position: absolute;
  padding: 0;
  width: 100%;
  left: 0;
  top: 48px;
}
.drop div {
  -webkit-transform: translate(0, -100%);
  -moz-transform: translate(0, -100%);
  -ms-transform: translate(0, -100%);
  transform: translate(0, -100%);
  -webkit-transition: all 0.5s 0.1s;
  -moz-transition: all 0.5s 0.1s;
  -ms-transition: all 0.5s 0.1s;
  transition: all 0.5s 0.1s;
  position: relative;
}
.drop li {
  display: block;
  padding: 0;
  width: 100%;
  background: #b4bad2 !important;
}

#marker {
  height: 6px;
  background: #b4bad2 !important;
  position: absolute;
  bottom: 0;
  width: 120px;
  z-index: 2;
  -webkit-transition: all 0.35s;
  -moz-transition: all 0.35s;
  -ms-transition: all 0.35s;
  transition: all 0.35s;
}

#main li:nth-child(1):hover ul div {
  -webkit-transform: translate(0, 0);
  -moz-transform: translate(0, 0);
  -ms-transform: translate(0, 0);
  transform: translate(0, 0);
}
#main li:nth-child(1):hover ~ #marker {
  -webkit-transform: translate(0px, 0);
  -moz-transform: translate(0px, 0);
  -ms-transform: translate(0px, 0);
  transform: translate(0px, 0);
}

#main li:nth-child(2):hover ul div {
  -webkit-transform: translate(0, 0);
  -moz-transform: translate(0, 0);
  -ms-transform: translate(0, 0);
  transform: translate(0, 0);
}
#main li:nth-child(2):hover ~ #marker {
  -webkit-transform: translate(120px, 0);
  -moz-transform: translate(120px, 0);
  -ms-transform: translate(120px, 0);
  transform: translate(120px, 0);
}

#main li:nth-child(3):hover ul div {
  -webkit-transform: translate(0, 0);
  -moz-transform: translate(0, 0);
  -ms-transform: translate(0, 0);
  transform: translate(0, 0);
}
#main li:nth-child(3):hover ~ #marker {
  -webkit-transform: translate(240px, 0);
  -moz-transform: translate(240px, 0);
  -ms-transform: translate(240px, 0);
  transform: translate(240px, 0);
}

#main li:nth-child(4):hover ul div {
  -webkit-transform: translate(0, 0);
  -moz-transform: translate(0, 0);
  -ms-transform: translate(0, 0);
  transform: translate(0, 0);
}
#main li:nth-child(4):hover ~ #marker {
  -webkit-transform: translate(360px, 0);
  -moz-transform: translate(360px, 0);
  -ms-transform: translate(360px, 0);
  transform: translate(360px, 0);
}
